As others have pointed out, changing the collation for a database is not simple.

However, if you need to change it it's probably because some comparisons between columns in your database and columns in #temp tables are failing.

I see a couple of options here:

1) Add "COLLATE DATABASE_DEFAULT" to each CREATE #temp TABLE statement and/or directly in the comparison predicate. Not easy, but it will make your application more robust.

2) Change the dev server collation. Obviously, it will be feasible only if you don't have other databases in the dev instance that require a different collation

3) Build a script to change the collation of every column in the restored database, as Lowell suggested.

Lots of pain, no matter which one you choose.